Enable player to speed up game

game.js

@@ -40,6 +40,8 @@ class Game {
         this.isMoving = false;
         this.isPaused = false;
         this.isGameOver = false;
+        this.speed = 1;
+        this.lastSpeedUp = 0;
 
         this.coinAngle = 0;
         this.mousePos = null;
@@ -156,6 +158,7 @@ class Game {
         }
 
         this.isMoving = true;
+        this.lastSpeedUp = Date.now();
 
         const dir = this.calcMouseAngle();
         const ballCount = this.ballCount;
@@ -172,6 +175,10 @@ class Game {
     }
 
     roundOver() {
+        this.speed = 1;
+        this.lastSpeedUp = Date.now();
+        this.elements.speedUpContainer.innerHTML = "";
+
         this.ballCount += this.newBalls;
         this.newBalls = 0;
         this.remainingBalls = this.ballCount;
@@ -264,6 +271,21 @@ class Game {
                 this.coinAngle -= 2 * Math.PI;
             }
 
+            if (this.isMoving && Date.now() - this.lastSpeedUp >= 10000) {
+                const button = document.createElement('button');
+                button.innerText = 'FASTER';
+                this.elements.speedUpContainer.innerHTML = "";
+                this.elements.speedUpContainer.appendChild(button);
+
+                button.addEventListener('click', () => {
+                    this.speed *= 2;
+                    button.remove();
+                });
+
+                this.lastSpeedUp = Date.now();
+            }
+        }
+
         if (!this.isPaused && !this.isGameOver) {
             requestAnimationFrame(() => this.update());
         }
@@ -278,6 +300,7 @@ class Game {
 
     play() {
         this.isPaused = false;
+        this.lastSpeedUp = Date.now();
         this.update();
         this.draw();
 
@@ -293,6 +316,7 @@ class Game {
     }
 
     destroy() {
+        this.elements.gameOverMenu.classList.remove('shown');
         this.removeEventListeners();
     }
 

index.html

@@ -29,7 +29,7 @@
             <h3 id="coin-count">0</h3>
         </div>
 
-        <div></div>
+        <div class="speed-up-container"></div>
     </div>
 
     <div class="game-container">